bone marrow

noun

Definition of bone marrow

  1. :  a soft highly vascular modified connective tissue that occupies the cavities of most bones and occurs in two forms:a :  one that is yellowish, consists chiefly of fat cells, and is found especially in the cavities of long bonesb :  one that is reddish, is the chief site of blood cell formation, and occurs in the normal adult in cancellous tissue especially of certain flat bones —called also red marrow

First Known Use of bone marrow

1850


BONE MARROW Defined for English Language Learners

bone marrow

noun

Definition of bone marrow for English Language Learners

  • : a soft substance that fills the bones of people and animals


BONE MARROW Defined for Kids

bone marrow

noun

Definition of bone marrow for Students

  1. :  a soft tissue rich in blood vessels that fills the spaces of most bones and includes one type that is red and produces red blood cells and white blood cells and another type that is yellow and contains fat


Medical Dictionary

bone marrow

noun

Medical Definition of bone marrow

  1. :  a soft highly vascular modified connective tissue that occupies the cavities and cancellous part of most bones and occurs in two forms:a:  a whitish or yellowish bone marrow that consists chiefly of fat cells and is found especially in the cavities of the long bones—called also yellow marrowb:  a reddish bone marrow that contains little fat, is the chief site of red blood cell and blood granulocyte formation, and occurs in the normal adult in cancellous tissue especially of certain flat bones—called also red marrow


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